1. Field of the Invention
This invention relates to a drive tower for a self-propelled irrigation system such as a center pivot or linear move irrigation system and more particularly to a tracked drive tower for those irrigation systems.
2. Description of the Related Art
Self-propelled irrigation systems such as center pivot and linear move systems normally employ a plurality of wheeled drive towers which support and propel the irrigation pipe over the area to be irrigated. The wheels of the drive towers frequently create deep wheel tracks in the field. Further, in some situations, the drive wheels slip and are unable to propel the irrigation system. In an attempt to solve the problems associated with wheeled drive towers, there have been some attempts at providing a drive tower wherein the same is propelled by an endless track much like a tank track or crawler tractor type. One such system is disclosed in U.S. Pat. No. 5,078,326. Other tracked-type systems for drive towers for irrigation systems are found in certain of the prior art cited during the prosecution of the above-identified patent.
Although tracked drive towers have been previously provided, it is believed that the tracked drive towers of the prior art suffer from certain disadvantages. It is believed that certain of the prior art devices suffer slippage between the drive wheels or track pulleys and the endless track. Further, it is believed that certain of the tracked drive towers of the prior art are overly complicated. Still another disadvantage of the prior art systems is that the belts wear readily due to the means of driving the same.